Electrolysis apparatus

ABSTRACT

A device for electrolytic production of hydrogen and oxygen, comprising: process lines for feed of water and electrolyte and withdrawal of the electrolysis products, an electrolyser, comprising a body with upper and lower covers made of electrically conducting material, short-circuited electrodes, one of which is located centrally in the electrolyser, and the other is formed by the inside surface of the body, and an electromagnetic system, comprising magnets, mounted above the upper and under the lower covers of the body, the electrolyser being rotatable relative to the magnets.

BACKGROUND OF THE INVENTION

This invention relates to the area of electrochemistry, namely todesigns of electrolysers for the production of hydrogen and oxygen bythe electrolysis of water.

There is a known installation for electrolysis of water in a centrifugalfield (Russian patent 2253700, publ. Jun. 10, 2005), comprising processlines for feed of water and starting electrolyte and withdrawal of theelectrolysis products, an electrolyser, consisting of acurrent-conducting body, upper and lower covers and electrodes, one ofwhich is mounted on a vertical shaft connected to a rotary drive, saidshaft having channels for supplying electrolyte solution into the bodyof the electrolyser and for withdrawing the electrolysis products, andthe other is formed by the inside surface of the body of theelectrolyser. The installation is equipped with a device fortransformation and distribution of electrical energy with an externalelectric circuit, connected electrically to the rotary drive of theshaft. The electrolyser is equipped with a device for distribution ofthe stream of circulating electrolyte solution, constructed fromelectrically-insulating material and located above the shaft-mountedelectrode, current supply and two stationary sliding contacts, connectedto the device for transformation and distribution of electrical energy.The drawback of the known installation is intensive wear of the brushesat high rotary speeds of the electrolyser. Moreover, the brush contactsintroduce additional resistance into the electric circuit of theelectrolyser, which hampers the electrolysis process. Furthermore, themagnitude of the current passing through the brush contacts is limited.

The document “Installation for decomposition of water by electrolysis”(Russian patent 2224051, publ. Feb. 20, 2004) describes apparatus havingprocess lines for feed of water and electrolyte and withdrawal of theelectrolysis products, an electrolyser, comprising a body mounted on ashaft connected to a rotary drive, said shaft having channels for supplyof electrolyte solution and withdrawal of the electrolysis products, achannel for withdrawal of the electrolyte solution, short-circuitedelectrodes, one of which is located on the shaft, and the other isformed by the inside surface of the body, and a heat exchanger, as wellas upper and lower bearing units, in which the shaft is positionedvertically. The external circuit for circulation of electrolyte solutioncontains an annular chamber of electrolyte solution with inside surfacein the form of a helix, fixed in the upper bearing unit, a sensor forpresence of electrolyte solution and a mixer of the electrolytesolution, connected to the lines for feed of electrolyte and water andthe channel for supply of electrolyte solution, the body of theelectrolyser is constructed from current-conducting material and isprovided with lower and upper covers made of current-conductingmaterial, a channel for withdrawal of electrolyte solution is providedin the upper cover and is equipped with a control valve, communicatingwith the annular chamber of electrolyte solution, the inside surface ofthe body is provided with at least one guide groove, the line for feedof water is equipped with a device for controlling water consumption,the line for withdrawal of the electrolysis products is equipped with adevice for pumping out the electrolysis products, the heat exchanger islocated in the external circuit for circulation of electrolyte solution,and the sensor for presence of electrolyte solution is connected to thedevice for controlling water consumption and the rotary drive of theshaft. The drawbacks of the known installation include the need for highworking speeds of rotation of the electrolyser, which makes the devicerather unsuitable for industrial use. Other drawbacks include complexityof design, and low productivity.

Embodiments of the present invention may have the advantages ofsimplification of design, decrease in working speed of rotation of theelectrolyser and increase in productivity.

SUMMARY OF THE INVENTION

One or more of the above problems may be solved in that the known devicefor electrolytic production of hydrogen and oxygen, containing processlines for feed of water and electrolyte and withdrawal of theelectrolysis products, an electrolyser, comprising a body with upper andlower covers made of electrically conducting material, mounted on ashaft connected to a rotary drive, said shaft having channels for supplyof electrolyte solution and withdrawal of the electrolysis products,short-circuited electrodes, one of which is located on the shaft, andthe other is formed by the inside surface of the body, moreover the linefor withdrawal of the electrolysis products contains, connected inseries, a device for pumping out the electrolysis products and aseparator, and the line for feed of water and electrolyte contains tanksfor water and electrolyte, a device for controlling water consumption,valves, mixer and heat exchanger, it is equipped with an magnetic(optionally electromagnetic) system, comprising a number of fixedpermanent magnets or electromagnets in the form of disks (or othershapes or cross-sections), mounted with opposite poles in parallel abovethe upper cover and under the lower cover of the body, a magneticcircuit, in the case of electromagnets, connected mechanically to them,with an exciting winding connected electrically to a pulse generator anda voltage transformer, on the line for withdrawal of the electrolysisproducts there is a gas analyser, the inlet of which is connected to theoutlet of the device for pumping out the electrolysis products, and theoutlet is connected to the device for controlling the water consumption,moreover the short-circuited electrode located on the shaft isconstructed in the form of a cylinder with radial channels.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example only, withreference to the accompanying drawings, in which:

FIG. 1 shows schematically an embodiment of the device; and

FIG. 2 shows a simplified plan view of an arrangement of magnets.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The installation shown in the drawing contains an electrolyser 1,comprising a cylindrical body or drum 2, made of electrically conductingnon-magnetic material with upper 3 and lower 4 covers made ofelectrically conducting magnetic material, mounted on vertical shaft 5,made of current-conducting non-magnetic material, in upper 6 and lower 7bearing units. Shaft 5 is connected to rotary drive 8 and on the insideit has channels for supply of electrolyte solution or water 9 and forwithdrawal of the electrolysis products 10. On shaft 5 inside theelectrolyser there is a short-circuited electrode 11 with radiallypositioned channels 12 (e.g. anode), made of electrically conductingnon-magnetic material. The inside surface of body 2 forms the otherelectrode (e.g. cathode). The position of the interface between theanode and the cathode is preferably chosen to provide balanced surfaceareas for the release of the electrolysis products. The channel for feedof electrolyte solution or water 9 is connected to the line for feed ofwater and electrolyte 13, with heat exchanger 14, mixer 15, to valve 16,to electrolyte tank 17, to valve 18, to the device for controlling waterconsumption 19 and to water tank 20. The heat exchanger 14 is alsoconnected to a drain valve 21. The channel for withdrawal of theelectrolysis products 10 is connected via the process line forwithdrawal of the electrolysis products 22 to the device for pumping outthe electrolysis products 23, connected to gas analyser 24, electricallyconnected to the device for controlling water consumption 19 and to theseparator 25 for separating the oxygen-hydrogen mixture into oxygen andhydrogen. The electrolyser is equipped with a permanent orelectromagnetic system, comprising upper 26 and lower 27 fixed magnets(e.g. in the form of disks), and, for the electromagnetic option,magnetic circuit 28 connected mechanically to them, exciting winding 29,connected electrically to a controllable pulse generator 30 and to acontrollable voltage transformer 31. The surfaces of the electrolyser incontact with the electrolyte are covered with special coatings, whichimprove the electrical properties of the electrically conducting partsand protect the materials from corrosion.

The device operates as follows. Electrolyte from electrolyte tank 17goes via the process line for feed of electrolyte 13 through the openvalve 16 into mixer 15, then into heat exchanger 14, and from therethrough the channel for feed of electrolyte solution 9, located on shaft5, into electrolyser 1. Valve 18 on the water feed line is closed. Oncethe electrolyser 1 has been filled with electrolyte solution, valve 16is closed and the rotary drive 8 of shaft 5 is switched on, causingelectrolyser 1 to rotate, accelerating it until the start of theelectrolysis process. Once the electrolysis process begins, the rate atwhich it continues will be expected to decrease due to conversion ofwater from the electrolyser 1 and the reduction of surface areaavailable for the passage of electricity. Control of the output rate iseffected by a signal from the gas analyser 24, which operates the devicefor controlling water consumption 19 through the process line for feedof water 13 into electrolyser 1. The installation goes into automaticmode for controlling the feed of water from water tank 20 through thedevice for controlling water consumption 19, the open valve 18, themixer of electrolyte solution 15, heat exchanger 14 and the channel forfeed of electrolyte solution 9 into electrolyser 1. In the rotatingelectrolyser 1, during production of hydrogen and oxygen the volume ofthe electrolyte solution and hence its concentration vary continually:the concentration of the electrolyte solution increases, and the volumedecreases. Each of the electrodes in electrolyser 1 can perform thefunction of anode or cathode depending on the chemical composition ofthe electrolyte used.

During rotation, under the action of centrifugal force an artificialgravitational field is created in electrolyser 1, under the action ofwhich the cations and anions in the form of hydrates, havingsubstantially different intrinsic mass, are separated. The heavier ions,e.g. cations, form, near the inside surface of body 2 (cathode), anegative electric space charge, which induces an adequate charge ofconduction electrons in body 2, made of current-conducting material. Thelight ions concentrate in the region between the cathode and anode 11,forming their own positive space charge, and if the magnitude of itspotential is sufficient to create an electric field capable of deformingthe hydrate shells of the light ions, the equilibrium that had beenestablished will be disrupted on anode 11. The light ions will approachthe surface of anode 11 and will be discharged. The heavy ions will alsogive up their charge to the cathode and a constant electric current willflow between the electrodes through the upper 3 and lower 4 covers andshaft 5, made of current-conducting materials, as in a short-circuitedcircuit. The ions of the electrolyte will be reduced, forming hydrogenand oxygen, and the electrolysis intermediates will enter into sidereactions with the water. The reduced hydrogen and oxygen will bedisplaced towards the centre of electrolyser 1 and will be sent to theconsumer in the form of oxygen-hydrogen mixture through the channel forwithdrawal of the electrolysis products 10, the device for pumping outthe electrolysis products 23 and gas analyser 24.

For separating the oxygen-hydrogen mixture into oxygen and hydrogen, theinstallation can be equipped with a separator 25, from which theseparated gases are sent to the consumers of oxygen and hydrogen. Insimilar known devices the electrolysis process takes place under theaction of a centrifugal field alone, which presupposes high angularfrequencies of rotation of the electrolyser (3000-5000 radians persecond). Technically this is difficult to accomplish. The proposedinstallation employs a magnetic system, which made it possible to lowerthe working angular frequencies of rotation of the electrolyser to(500-1500 radians per second) and increase the productivity of theelectrolyser by a large factor.

By supplying the electromagnetic winding 29 from a controllableconstant-voltage transformer 31, it is possible to act upon anelectrically charged particle moving in a constant magnetic field with aforce:

F=B·V·q,

where

-   B is magnetic induction, TI;-   V is the linear velocity, m/s;-   q is the magnitude of the electric charge, K.

The vectors of the forces acting on the negative and positive particlesare directed opposite and perpendicular to the vector of the linearvelocity, so that the heavy ions go towards the periphery of theelectrolyser, and the light ones go towards the centre.

Connection of the electromagnetic winding 29 to the controllable pulsegenerator 30 makes it possible to act additionally on the chargedparticles at the resonance frequency that promotes their separation. Thefrequency and relative duration of the generator pulses are selected inrelation to the chemical composition of the electrolyte solution, so asto enter into resonance corresponding to the given electrolyte. Byutilizing the resonance effect, further lowering of the working angularfrequencies of rotation of the electrolyser and increase of itsproductivity become possible.

The process of decomposition of water into hydrogen and oxygen byreduction of their ions is accompanied by a decrease in enthalpy of theelectrolyte solution, as a result of which the temperature of thesolution falls continually, and if the heat losses are not compensated,the solution will freeze and the process will come to a halt. For thisreason it is necessary to heat the solution. For this purpose, a heatexchanger 14 is installed in the process line for supply of water.Thermal energy can be supplied to heat exchanger 14 in the form ofexhaust gases or antifreeze from an internal combustion engine or insome other form. To meet safety requirements the installation can beequipped with a protective casing. Transformation of mechanical,electrical and thermal energy to chemical energy takes place in theproposed device.

The gas analyser 24 used can be of the type AVP-02, or AKPN-02, alsoperforming the function of sensor. An electric vacuum pump can be usedas the device for withdrawal of the electrolysis products 24, with aTP-3R voltage transformer as the controllable voltage transformer 31,and a solenoid valve as the device for controlling water consumption 19.

FIG. 2 shows in plan view one suitable arrangement of the magnets. FIG.2 shows a simplified view of the apparatus of FIG. 1 from the directionof arrow 40 of FIG. 1. In FIG. 2 the drum 2 of FIG. 1 is shown at 51 andthe shaft 5 of FIG. 1 is shown at 52. The magnets 50 are located on thedrum 51. The magnets are spaced evenly around the shaft 52, and arepreferably located at equal distances therefrom. The magnets may bepermanent magnets or electromagnets. Preferably, the magnets arearranged in pairs, so that diametrically opposite each magnet there isanother magnet equally spaced from the shaft 52. Any suitable number ofpairs of magnets may be used.

The proposed device makes it possible to increase the productivity ofthe installation, lower the working angular frequencies of rotation ofthe electrolyser and simplify the design. The device can be manufacturedusing traditional constructional materials, components and knownelectrolytes and can be used in units of internal combustion engines ofmeans of transport, increasing their fuel economy, with steam turbinesof thermal and nuclear power stations, for utilization of industrialheat in metallurgy etc.

The applicant hereby discloses in isolation each individual featuredescribed herein and any combination of two or more such features, tothe extent that such features or combinations are capable of beingcarried out based on the present specification as a whole in the lightof the common general knowledge of a person skilled in the art,irrespective of whether such features or combinations of features solveany problems disclosed herein, and without limitation to the scope ofthe claims. The applicant indicates that aspects of the presentinvention may consist of any such individual feature or combination offeatures. In view of the foregoing description it will be evident to aperson skilled in the art that various modifications may be made withinthe scope of the invention.

1. A device for electrolytic production of hydrogen and oxygen,comprising: process lines for feed of water and electrolyte andwithdrawal of the electrolysis products, an electrolyser, comprising abody with upper and lower covers made of electrically conductingmaterial, short-circuited electrodes, one of which is located centrallyin the electrolyser, and the other is formed by the inside surface ofthe body, and an electromagnetic system, comprising magnets, mountedabove the upper and under the lower covers of the body, the electrolyserbeing rotatable relative to the magnets.
 2. A device as claimed in claim1, wherein the electrolyser is mounted on a shaft connected to a rotarydrive, said shaft having channels for supply of electrolyte solution andwithdrawal of the electrolysis products.
 3. A device as claimed in claim1, wherein the opposite poles of the magnets are mounted in parallel. 4.A device as claimed in claim 1, wherein the magnets are in the form ofdisks.
 5. A device as claimed in claim 1, wherein the line forwithdrawal of the electrolysis products contains, connected in series, adevice for pumping out the electrolysis products and a separator, andthe line for feed of water and electrolyte contains tanks for water andelectrolyte, a device for controlling water consumption, valves, a mixerand a heat exchanger.
 6. A device as claimed in claim 1, wherein one ormore of the magnets are electromagnets.
 7. A device as claimed in claim6, comprising a magnetic circuit connected mechanically to the magnetswith an exciting winding, connected electrically to a pulse generatorand a voltage transformer.
 8. A device as claimed in claim 1, comprisinga gas analyser on the line for withdrawal of the electrolysis products,the inlet of the gas analyser being connected to the outlet of a devicefor pumping out the electrolysis products, and the outlet of the gasanalyser being connected to the device for controlling the waterconsumption.
 9. A device as claimed in claim 1, wherein theshort-circuited electrode located on the shaft is constructed in theform of a cylinder with radial channels.
 10. A device as claimed inclaim 1, wherein the magnets are configured for assisting theelectrolysis of fluid in the electrolyser.